Hydro-Jet-assisted laparoscopic cholecystectomy: A prospective randomized clinical study

Hydro-Jet–assisted laparoscopic cholecystectomy: A prospective randomized clinical study Hodjat Shekarriz, MD, Bijan Shekarriz, MD, Peter Kujath, MD, Christian Eckmann, MD, Conny Bürk, MD, Andreas Comman, MD, and Hans-Peter Bruch, MD, Lübeck, Germany; and Syracuse, NY

Background. A new dissection technique with high-pressure water stream (Hydro-Jet) has recently been applied for selective dissection during various surgical procedures. The aim of this study was to compare Hydro-Jet with the conventional technique for laparoscopic cholecystectomy. Methods. Eighty patients were randomized to undergo laparoscopic cholecystectomy with standard (n = 40) or Hydro–Jet–assisted (n = 40) dissection techniques. The rates of intraoperative complications, including blood loss and injury to the adjacent organs, were compared between the groups. The versatility of this technique and the features of surgical dissection were also evaluated and compared. Results. Laparoscopic cholecystectomy was successfully completed in all subjects. The mean operative times were 78 minutes (range, 52-120 minutes) and 81 minutes (range, 45-135 minutes) for Hydro-Jet versus conventional dissection, respectively (P = not significant). Complications included gallbladder perforation in 15% and 30% (P < .1) and liver laceration in 0% and 10% (P < .04) with Hydro-Jet and conventional techniques, respectively. Increased hemorrhage from the gallbladder bed that necessitated fulguration occurred in 12 patients with the conventional technique as compared with none in the Hydro-Jet group (P < .001). Hydro-Jet resulted in a selective dissection of connective tissue preserving blood vessels and the cystic duct. The continuous water flow allowed a clear view for the operator, and the dissection was performed in a relatively bloodless field. The ease of blunt dissection with the bent-tip dissector represents another advantage. Conclusion. This study shows that Hydro-Jet dissection represents an excellent alternative to the conventional technique for laparoscopic cholecystectomy. The improved anatomic dissection combined with an almost bloodless operating field as the result of continuous water flow decreased the rate of dissectionrelated complications. (Surgery 2003;133:635-40.) From the Department of Surgery, University of Lübeck, Lübeck, Germany; and the Department of Urology, SUNY, Upstate Medical University, Syracuse, NY

LAPAROSCOPIC CHOLECYSTECTOMY OFFERS the advantage of being a less morbid procedure with shorter convalescence time as compared with standard open surgery.1,2 Despite these advantages, surgical complications may occur. In large European and United States series, complications included bleedings (0.2% to 4.3%), bile duct injuries (0.2% to 1%), and bile duct fistulas (0.2% to 1%).1-4 Accepted for publication March 1, 2003. The authors have no financial interest in the company making the Hydro-Jet Instruments, and there has been no industrial support for this study. Reprint requests: Bijan Shekarriz, MD, Department of Urology, SUNY, Upstate Medical University, Syracuse, NY 13210. © 2003 Mosby, Inc. All rights reserved. 0039-6060/2003/$30.00 + 0 doi:10.1067/msy.2003.155

Moreover, stone loss and incidental perforation of the gallbladder are common complications (up to 50%) of laparoscopic cholecystectomy.5-7 A conversion to open surgery may be necessary in 2% to 8% of cases.1-4 These complications usually occur when the operating field is obscured by bleeding from dissection. Furthermore, surgical adhesions from prior procedures may make the dissection difficult and contribute to increased intraoperative complications, such as hemorrhage and conversion to an open procedure. Therefore, a bloodless operative field and versatile dissection techniques are critical for a successful laparoscopic procedure. To improve the dissection and reduce the dissection-related complications, we have recently used a new technology with a high-pressure water stream (Hydro-Jet). In the industrial arena, the use of high-pressure water flow (1000 to 2000 atm) has SURGERY 635

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Table. Technical data: Hydro-Jet generator and probe Helix Hydro-Jet Pressure range Probe diameter Pressure mode Pressure control Water velocity Size Weight

0-150 atm (0-2175 psi) 120 µm inner radius Electrohydraulic Foot pedal 32.9 mL/min (120 µm probe, 30 atm) 600 (width)
1470 (height)
810 (depth) mm 95 kg

been used for the processing of different materials, such as metals, ceramic, wood, and glass.8 In the surgical field, this technology has also been successfully applied for excision of liver parenchyma, corneal surgery, neurosurgery, and renal surgery.9-14 In the field of laparoscopic surgery, initial experimental and clinical data for liver resection and renal-sparing surgery have been encouraging.15-18 We have recently reported our experience with laparoscopic cholecystectomy in a porcine model.19 In this model, a comparison between the Hydro-Jet–assisted cholecystectomy and standard dissection showed superior dissection with decreased complication rates. Encouraged by our initial experimental studies, we have conducted the first prospective clinical study with this technology for laparoscopic cholecystectomy. The goal of this study was to investigate the use of this novel technique in humans and compare the results with the standard dissection technique. PATIENTS AND METHODS Subjects. Eighty patients were randomized into 2 groups (40 patients each) to receive either standard or Hydro-Jet–assisted laparoscopic cholecystectomy. Patients were accrued consecutively as they were seen at the university hospital over the study period. All procedures were performed by 1 surgical team. The primary surgeon had experience with more than 100 conventional and 20 Hydro-Jet–assisted cholecystectomies. Patients were randomized on the basis of a standard randomization table provided by the department of statistics. The total number of patients was based on the power analysis performed by our statistician. The inclusion criteria included cholelithiasis with clinical indication for cholecystectomy and patient age of more than 16 years. Exclusion criteria included acute cholecystitis. The clinical diagnosis of acute cholecystitis was made with the presence of fever and leukocytosis and elevated C-reactive protein, which is

Fig 1. Laparscopic Hydro-Jet probe.

a reliable finding in our experience. Sonographic evidence of acute cholecystitis was also used as exclusion criterium. Chronic cholecystitis was no contraindication for the study. The outcome measures were intraoperative parameters including operative time and hemorrhage and complications. Hydro-Jet generator and dissection probe. A Helix Hydro-Jet (A. Pein Medizintechnik, Schwerin, Germany) generator was used. Technical data are summarized in the Table. This is a newer generation device that was originally used for liver surgery. The water pressure can be adjusted via a foot pedal in 1-atm and 5-atm increments, with a maximum of 150 atm (2175 psi). Normal saline solution (0.9%) was the medium used at a temperature of 20°C to 22°C. Actual pressure was continuously monitored during the operation. A maximum pressure of 30 atm was used. We arrived at this pressure on the basis of our initial experience in pigs. Hand pieces for different sized probes (diameter, 80-300 µm) with or without integrated suction devices are available. A modified dissection probe (A. Pein) with an angled tip to extend its use as a water-jet applicator and for blunt dissection was used (Fig 1). The degree of angulation of the tip of the probe is approximately 40 degrees, with an inner diameter of 120 µm. A separate bipolar thermoapplicator and probe for coagulation was applied as needed during the procedures. Surgical technique. With Hasson’s technique, a pneumoperitoneum (intraabdominal pressure of 15 mm Hg) was created. A subumbilical port was used for camera application. Three further ports, subxyphoid (10 mm) and right and left upper abdomen (5 mm), were then placed under direct vision. The gallbladder was then grasped with a grasping forceps and brought into a ventral position for further dissection. The surgical steps were

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identical for this part of the operation. Thereafter, either a conventional dissection or a Hydro-Jet— assisted dissection technique was used. Bipolar cautery was used for both techniques. Conventional dissection. Conventional laparoscopic cholecystectomy was performed as previously described in humans.7,20 The technique for cholecystectomy in the conventional group included the exclusive use of bipolar coagulation and scissors. Both dissection of the gallbladder off of the liver bed and isolation of hilar structures were performed with sharp and blunt dissection with bipolar instruments. Briefly, blunt and sharp dissection were used to identify the cystic duct and cystic artery, which were then individually clipped. Smaller bleeding vessels were coagulated with a bipolar cautery. Further dissection of the gallbladder off of the liver bed was then performed. The gallbladder was removed, and the bleeding points of the liver bed were controlled with bipolar cautery. Hydro-Jet technique for dissection. Initially, water was applied in the subserosal layer at the level of gallbladder infundibulum and cystic duct junction with the Hydro-Jet probe from a distance of a few centimeters with a maximum pressure of 30 atm. This was performed in a retrograde (toward fundus) and antegrade (along the cystic duct) fashion, resulting in an expansion of the subserosal space and creation of surgical planes. Further application of water was performed after insertion of the probe into the subserosal space. The serosa was then bluntly dissected along the cystic duct and at the lateral and medial edge of the gallbladder with the probe. Blunt dissection of the cystic duct and cystic artery was done with the bent tip of the probe (Fig 2). These structures then were clipped and transected. Finally, the gallbladder was dissected in a retrograde fashion with application of Hydro-Jet and blunt dissection. Statistical analysis. The mean values were compared with a 2-tailed t test. The Pearson χ2 test was used to compare the differences between the groups with regard to various intraoperative parameters. A statistical software program (SAS; Cary, NC) was used for this analysis. RESULTS There were 32 women and 8 men in the HydroJet group, with a mean age of 53.8 years (range, 35 to 70 years). In the standard dissection group, there were 29 women and 11 men, with a mean age of 56.4 years (range, 37 to 72 years), respectively. No statistically significant differences were seen between the groups with regard to age or gender.

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Fig 2. Tissue selectivity of Hydro-Jet dissection results in preservation of cystic duct and artery and subsequent blunt dissection with bent-tip probe.

Comparison of operative time and surgical complications. Overall, laparoscopic cholecystectomy was successful in all subjects, and no conversion to open surgery was necessary. The mean operative time was 78.6 minutes (range, 52-120 minutes) in the Hydro-Jet and 81.9 minutes (range, 45-135 minutes) in the control group, respectively. These differences were not statistically significant. No major vascular injury from dissection was noted in either of the surgical groups. Increased hemorrhage from the liver bed after dissection of gallbladder did not occur in the Hydro-Jet group, and 12 patients in the conventional group had increased hemorrhage necessitating fulguration (P < .001). For objective assessment of the need for coagulation to control small hemorrhage during the procedure, we recorded the number of times that coagulation was needed in each group. The number of coagulations was used as an indicator for dissection in the correct surgical plane. The mean number of times coagulation was used in the Hydro-Jet group was 25.8 (range, 5-55) per case compared with 50.35 (range, 15-120) per case (P < .015). Gallbladder perforation occurred in 6 (15%) and 12 (30%) patients in the Hydro-Jet and conventional dissection groups, respectively (P < .1). For this study, only the dissection-related perforations were included. Liver lacerations were all dissection-related. Minor liver laceration necessitating hemostatic agents such as fibrin glue occurred in 4 patients (10%) in the conventional group and none in the Hydro-Jet group (P < .04). No other organ injuries occurred. The mean normal saline solution used during Hydro-Jet dissection was 195 mL (range, 150-250

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was dissected practically with blunt dissection. Furthermore, continuous water flow allowed a clear view for the operator.

Fig 3. A, Subserosal space before application of Hydro-Jet. Probe is brought in close proximity to outer connective tissue and Hydro-Jet is applied. B, Expansion of subserosal tissues and preservation of vessels. Water penetrates soft tissue planes, and large vessels are preserved with 30 atm pressure. C, Blunt dissection with bent tip of probe after water application facilitates isolation of vascular structures and cystic duct.

mL). Overall, the dissection time was shorter (although not statistically significant) and the complication rate was lower with Hydro-Jet. Technical features and advantages of Hydro-Jet. Fig 3 shows the principle of Hydro-Jet dissection. As shown in Fig 3, Hydro-Jet dissection had tissue selectivity. Application of water around and beneath the serosal layer resulted in expansion of the subserosal space and creation of surgical planes (Fig 3, A and B). During dissection of the cystic duct and artery, the thin stream of high-pressure water allowed selective separation of surrounding connective tissue components from the vessels and bile duct. Water displaced fibrous and collagenous tissue, leaving these structures intact. After removal of the gallbladder, the liver bed was almost free of bleeding and subsequent hemostasis was not necessary. With the combined Hydro-Jet dissection and the angled tip dissector (Fig 3, C), the gallbladder

DISCUSSION Dissection-related complications during laparoscopic cholecystectomy may result in hemorrhage and injury to adjacent organs, including the bile duct. These complications may consequently result in conversion to laparotomy.1-7 In a recent review, a conversion rate of 5.3% was reported and the level of surgical experience was a prognostic factor.21 Today, an increasing number of young surgeons are performing this operation. Although the learning curve improves with time, in the beginning, complication rates may be higher. In a retrospective review of 932 laparoscopic cholecystectomies from University of Lübeck, the conversion rate was 3.8% (unpublished data). Increased hemorrhage necessitating coagulation was noted in 25%, of which 45% were related to the liver bed. The source of the remaining bleeding was cystic artery (16%) and port/access-related bleeding (9%). A gallbladder perforation was reported in 31%, with loss of calculi in 7.4%. Liver injury was noted in 16.6% and necessitated increased coagulation and the use of hemostatic agents, such as fibrin glue. Finally, intraoperative bile duct injury was reported in 3 patients (0.3%). These dissection complications mainly occur when the operative field is obscured by hemorrhage and adhesions from previous operations or the presence of acute inflammation.21 In our experience, increased adhesions requiring more extensive dissection were noted in 48% of the 932 patients. Therefore, it is apparent that methods to improve the dissection technique may result in improved surgical outcomes. Hydro-Jet and hydrodissection should not be confused. The principle of hydrodissection is the use of a stream of water (pressure, 200-600 mm Hg) to expand and delineate surgical planes.22-24 Nezhat et al22 described a technique for hydrodissection with a suction-irrigation probe (5-mm diameter) with injection of normal saline solution into the subperitoneal space to enter the retzius space. Ostrzenski23 applied this technique to develop tissue planes during laparoscopic hysterectomy. Hydrodissection was also used for laparoscopic cholecystectomy and lysis of adhesions, resulting in fewer complications and faster dissection.24,25 Although it is similar in principle, the Hydro-Jet technology uses an extremely thin high-pressure stream of water (30 atm in our study) that can be used for both blunt dissection and cutting. The application of water between tissue layers creates surgical

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planes. Moreover, the high-pressure stream of water can be used as a sharp knife to cut parenchymal organs, depending on the tissue density and the pressure used. Papachristou and Barters9 first used this technology for liver resections in dogs. Vessels and bile ducts were preserved. Recently, Piek et al11 described their clinical experience for dissection of brain parenchyma with Hydro-Jet. With a maximum pressure of 7 atm, small vessels could be preserved. In this context, we have used Hydro-Jet technology for a variety of laparoscopic surgical procedures, including laparoscopic cholecystectomy and nephrectomy.17-19 We have recently reported our experimental data with this technology for laparoscopic cholecystectomy.19 In that study, the use of this technique resulted in decreased complication rate and improved anatomic dissection as compared with standard dissection techniques. This clinical study confirms our initial experimental data. In this study, the use of the Hydro-Jet–assisted technique for laparoscopic cholecystectomy allowed precise anatomic dissection. The combination of blunt dissection (with the probe) and the sharp dissection of the soft tissue with the ultra-thin highpressure water stream resulted in creation of clear dissection planes and isolation of vascular structures and the cystic duct. The tissue selectivity of the Hydro-Jet significantly reduced minor vascular hemorrhage and the need for coagulation. This is reflected in the overall lower rate of liver bed bleeding with this technique as compared with standard dissection technique. With the Hydro-Jet technique, after removal of the gallbladder, the liver surface was almost free of bleeding, and no or minimal subsequent hemostasis was needed. In contrast, frequent coagulation of the gallbladder bed was necessary with conventional dissection. Moreover, liver lacerations necessitating hemostasis occurred only in 4 patients in the conventional group. Similarly, the rate of gallbladder perforations, which reflects dissection in a wrong plane, was twice as high in the conventional group (30% vs 15%). The dissecting effect depends on the tissue density, pressure used, and duration of application. With the 30-atm pressure for cholecystectomy, the HydroJet has tissue selectivity. Vessels and bile ducts contain more dense collagenous tissue and therefore withstand Hydro-Jet application without damage at this pressure. A clear operative field as the result of continuous water flow is another advantage of Hydro-Jet dissection. With this technique, the dissection was performed in a relative bloodless field. Therefore, this technique makes the operation easier and less challenging for the less experienced surgeon. The coag-

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ulation quality is similar to conventional technique. The gallbladder is moved cranially and ventrally. There is no pooling of saline solution in the area of dissection. Therefore, there is no difficulty with coagulation. A disadvantage of Hydro-Jet is that the backspray of water can obscure vision and may occur if the camera is held too close to the tissue during water application. This occurred 2 to 3 times during each procedure in our experience. This can be reduced and avoided with a larger distance between the lens and the tissue during water application, and it did not result in any significant delay. In contrast, the lower operative time with this technology is related to easier dissection and no need for changing instruments when dissection and irrigation are necessary simultaneously. The learning curve for Hydro-Jet technique is steep and only a short time period is necessary. We performed 30 laparoscopic cholecystectomies in pigs before human application. Before this study, we had performed 20 laparoscopic cholecystectomies with Hydro-Jet in humans. The issue of cost also needs to be addressed. We did not perform a formal cost comparison analysis with this technology for this initial study. However, current use of this technology is associated with increased surgical costs, including device and disposable materials. Whether this cost increase can be justified with improved surgical dissection and decreased complication rates remains to be elucidated. The relative high costs of device and disposable materials may be one reason for the fact that this technology has not been widely adopted. The use of this technology for only one surgical application may not be cost-effective. Therefore, multiple applications at one institution would increase the advantages and result in decrease costs. Currently, in centers where this technology is used, other surgical applications such as liver surgery and nerve-sparing procedures (prostatectomy, lymphadenectomies) are also performed. Further studies including cost comparisons are necessary to assess the financial burden of this technology. In summary, we describe the initial prospective randomized study comparing Hydro-Jet–assisted and standard dissection techniques for laparoscopic cholecystectomy. In our experience, the tissue selectivity of Hydro-Jet resulted in an improved anatomic dissection and decreased the complication rate. Therefore, this technology is an excellent alternative to conventional dissection technique. We favor the use of this technology for laparoscopic cholecystectomy and other surgical procedures to improve anatomic dissection.

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REFERENCES 1. Gadacz TR. U.S. experience with laparoscopic cholecystectomy. Am J Surg 1993;165:450-4. 2. Laparoscopic cholecystectomy: the European experience. Am J Surg 1993;165:444-9. 3. Lee VS, Chari RS, Cucchiaro G, Meyers WC. Complications of laparoscopic cholecystectomy. Am J Surg 1993;165:527-32. 4. Deziel DJ. Complications of cholecystectomy. Incidence, clinical manifestations, and diagnosis. Surg Clin North Am 1994;74:809-23. 5. Krämling HJ, Lange V, Heberer G. Aktueller Stand der Gallensteinchirurgie in Deutschland. Der Chirurg 1993;64:295-302. 6. Peiper M, Emmermann A, Rogiers X, Brölsch Ch E. Stenosierung des Ductuc Choledochus durch Metall-Clips nach laparoskopiacher cholecystektomie. Der Chirurg 1994;65:217-20. 7. Dubois F, Berthelot G. Laparoscopic cholecystectomy: historical perspective and personal experience. Surg Laparosc Endosc 1991;1:52-7. 8. Summers DA. Waterjetting technology. London: Spon; 1995. 9. Papachristou D, Barters R. Resection of the liver with a water jet. Br J Surg 1982;69:93-4. 10. Hata Y, Sasaki F, Takahashi H, Ohkawa Y, Taguchi K, Une Y, et al. Liver resection in children, using a water-jet. J Pediatric Surg 1994;9:648-50. 11. Piek J, Wille C, Warzok R, Gaab MR. Waterjet dissection of the brain: experimental and first clinical results, technical note. J Neurosurg 1998;89:861-4. 12. Terzis AJ, Nowak G, Rentzsch O, Arnold H, Diebold J, Baretton G. A new system for cutting brain tissue preserving vessels: water jet cutting. Br J Neurosurg 1989;3:361-5. 13. Lipshitz I, Bass R, Loewenstein A. Cutting the cornea with a waterjet keratome. J Refract Surg 1996;12:184-6. 14. Penchev RD, Kjossev KT, Lasanoff JE. Application of a new water jet apparatus in open hepatobiliary surgery: hepatic

15.

16.

17.

18.

19.

20. 21.

22.

23. 24.

25.

resection, cholecystectomy, common bile duct lavage. Int Surg 1997;82:182-6. Baer HU, Metzger A, Barras JP, Mettler D, Wheatley AM, Czerniak A. Laparoscopic liver resection in the large white pig- a comparison between waterjet dissector and ultrasound dissector. Endosc Surg Allied Technol 1994;2:189-93. Rau HG, Meyer G, Jauch KW, Cohnert TU, Buttler E, Schildberg FW. Leberresektion mit dem wasser-jet: Konventionell und laparoscopisch. Chirurg 1996;67:546-8. Shekarriz B, Shekarriz H, Upadhyay J, Wood DP, Bruch HP. Hydro-jet dissection for laparoscopic nephrectomy: a new technique. Urology 1999;54:964-6. Shekarriz H, Shekarriz B, Upadhyay J, Wood DP, Bruch HP. Hydro-Jet asssisted laparoscopic partial nephrectomy: initial experience in aporcine model. J Urol 2000;163:1005-8. Shekarriz H, Shekarriz B, Upadhyay J, Comman A, Markert U, Burk CG, et al. Hydro-Jet assisted laparoscopic cholecystectomy: initial experience in a porcine model. JSLS 2002;6:53-8. Asbun HJ, Rossi RL. Technique of laparoscopic cholecystectomy. Surg Clin North Am 1994;74:755-75. Delaitre B, Testas P, Dubois F, Mouret P, Nouaille JM, Suc B, et al. Complications of cholecystectomy by laparoscopic approach. Apropos of 6512 cases. Chirurgie 1992;118:92-9. Nezhat CH, Nezhat F, Seidman DS, Nasserbakht F, Nezhat C, Roemisch M. A new method for laparoscopic access to the space of retzius during retropubic cystourethropexy. J Urol 1996;155:1916-8. Ostrzenski A. A new laparoscopic abdominal radical hysterectomy. Eur J Surg Oncol 1996;22:602-6. Naude GP, Morris E, Bongard FS. Laparoscopic cholecystectomy facilitated by hydrodissection. J Laparoendosc Adv Surg Tech A 1998;8:215-8. Bokey EL, Keating JP, Zelas P. Hydrodissection: an easy way to dissect anatomical planes and complex adhesions. Aust N Z J Surg 1997;67:643-4.